Automatic control means for mechanical refrigerators



June 1, 1937. R.. R. NYDEGGER 2,082,023 AUTOMATIC CONTROL MEANS FORMECHANICAL REFRIGERATORS Origi nal Filed July 29, 1932 2 Sheets-Sheet 1INVENTOR ATTORN EYS June 1, 1937. R R7 NYDEGGER 2,082,023

AUTOMATIC CONTROL MEANS FOR MECHANICAL REFRIGERATORS Original Filed July29, 1932 2 Sheets-Sheet 2 I 2 20 29 7/32 I f]: 4

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ATTORNEYS Patented June 1, 1937 UNITED STATES PATENT OFFICE.

AUTOMATIC CONTROL MEANS FOR MECHANICAL REFRIGERATORS Roland R. Nydegger,Wilmington, Del.

Original application July 29, 1932, Serial No. 626,012. Divided and thisapplication April 4, 1933, Serial No. 664,321. Renewed October 24, 193611 Claims. (01. 20036) An important object of the present invention andstop the motor in response to temperature is to provide a satisfactoryapparatus for autochanges in the freezing unit when said switch ismatically interrupting the operation of a meclosed, an overloadprotective device and a startchanical refrigerator at a predeterminedtime ing relay. My invention involves no change in to permit the ice tomelt from the freezing unit; this control device and detail illustrationof the to provide such an apparatus which is conlatter is thought to beunnecessary. My autoveniently pre-settable to select the time fordematic control device is connected in circuit with icing and also todetermine the duration of the the standard control device D in a mannerto de-icing period; to provide a clock-controlled enable either deviceto be operated without inapparatus which is pre-settable to select anyday terference from the other. 10 of the week and any time of theselected day The automatic control device includes a clock for de-icing;and to provide such an apparatus mechanism l driven by an electric motor2. The designed for convenient operative connection to clock mechanismmay be of any suitable form a standard form of mechanical refrigerator.and it is thought to be unnecessary to illustrate Other objects of theinvention will appear it in detail. It has an arbor 3 which is rotated15 hereinafter. one full turn in a weeks time by the motor- In thedrawings, Fig. 1 is a front view of a driven mechanism. Two disk-likeelectrical constandard form of electrical refrigerator, equipped tacts 4and 5 are fixed to rotate with the arbor.

with my automatic control device; Also fixed to rotate with the arborare two ra- Fig. 2 a top plan View of said refrigerator and diallyextending contact fingers 6 and I. These control device; fingers aredisposed in permanent diametrical Fig. 3 a front View of the controldevice upon relation. The finger E is electrically connected, a largerscale; through the arbor, with the contact 4. The con- Fig. 4 a verticalsection on the line 4--4 of tact 5 and finger l are electricallyconnected Fig. 3 and showing diagrammatically the operawith each other,but insulated from the arbor, 25 tive connections of the control devicewith the the contact 4 and the finger 6 by insulation sleeves mechanismof the refrigerator which circulates 8 and 9. the freezing fluid; Inadvance of the contact fingers 6 and 'l are Fig. 5 a section on the line5-5 of Fig. 4 showtwo metal electrical contact plates l6 and H. 90 ingthe cooperation of the clock-driven electrical Plate I6 is of fiatannular form and has a raised contacts with the manually adjustablecontacts arcuate portion at its rear face forming a conto interrupt therefrigeration; and tact l2 engageable by the contact finger 1. PlateFig. 6 a view similar to Fig. 5 showing one of H is of circular diskform and its edge margin the contacts adjusted to vary the period ofinbears against the rear face of the plate 19 around terruption. themargin of the aperture therein. Plate ll 35 This application is adivision of my co-pendalso has a raised arcuate portion forming an ingU. S. patent application, Serial No. 626,012, electrical contact l3engageable by the contact filed July 29, 1932. finger 6. The plates aredisposed concentric with The automatic control device is illustrated inthe axis of the arbor, and the arcs of the plate connection with acommercial form of electricontacts I2 and l3subtend the same anglearound 40 cally operated refrigerator R having mounted said'axis. In thepresent instance said angle is upon the top of its cabinet a bank ofcondensing that through which the arbor and the radial coils C for therefrigerant fluid and a comprescontact fingers are rotated in a periodof twelve sor unit enclosed by said bank and comprising hours. The anglemay be varied, however.

an electric motor M and a pump P driven by Directly in advance of thecontact plates l0 and 45 said motor, as shown diagrammatically in Fig.II is a circular glass panel i4 having a central 4. The pump has theusual fluid connections, circular aperture. An annular dial plate l5bears not shown, with the condenser coils and with against the forwardface of said panel and has a the freezing unit F to withdraw therefrigerant circular relieved portion rotatably fitted in the fluid fromthe freezing unit, compress the fluid, panel aperture. A circular dialplate 16 of less 50 deliver it to the coils and thence back to thediameter than plate i5 is rotatably mounted on freezing unit. Ordinarilythe operation of the the latter and the inner edge of the plate !5 andmotor M is controlled by a control device D which the outer edge of theplate 16 have a rabbeted includes a manually operable switch to open andinterfit, with the plate I6 forwardly overlapping close the motorcircuit, a thermostat to start the plate 15. Centrally the plate I5 hasa forwardly projecting knob I! for rotating it. The knob is hollow andwithin it is a fore-andaft tension spring I8 having its forward endanchored to the knob and its rear end anchored to the contact plate II.The tension of said spring holds the plate II in frictional engagementwith the plate IIJ, holds the dial plate I6 in frictional engagementwith the dial plate I5 and holds the contact plate I and the dial plateI in frictional engagement with the glass panel I4, to yieldably resistrotation of said parts. The dial plates are made of insulating material.A pin I9 locks the plates I0 and I5 to rotate together, and the plate I5has a forwardly projecting bead around its outer edge to grasp forturning said plates. Another pin 20' locks the plates II and I6 torotate together. All of the plates are concentric with the axis of theclock arbor. By rotation of both dial plates and their connected contactplates in unison the contacts I2 and I3 are positioned so that thecontact fingers 6 and I will engage them at a selected time, and byrotation of the dial plate I5 and its connected contact plate I0independently of the other plates, the contact I3 is shifted relativelyto the contact I2 to vary the duration of contact of the fingers withthe contacts I2 and I3 simultaneously. These adjustments will bedescribed more specifically hereinafter.

Back of the contact plates I0 and II is a dial plate 2| bearing acircular time scale 22 visible through the glass panel and over the edgeof the dial plate I5. This scale has graduations and designations forthe days of the week, and graduations indicating the hours of each day.The contact finger I is extended to form a hand or pointer traversingthe scale, and the contact plate 9 has a pointer 23 selectivelyregistrable with any of the scale graduations to pro-select the day andhour of the de-icing period.

The degree of rotation of the dial plate I6 rel atively to the dialplate I5 is indicated by two circular scales 24 and 25, on plates I5 andI6 respectively. Scale 24 has a series of equally spaced graduationsnumbered from 0 to 12. Scale 25 also has a series of graduationssimilarly numbered but with the space therebetween exceeding the spacebetween the graduations of scale 24 by an angular extent around the axisof the arbor equal to one-twelfth of the angle subtended by the arcuatecontact I2 or by the contact I3. Therefore, when corresponding numbersof the two scales are registered the contact fingers 6 and I will remainin simultaneous engagement with the contacts I2 and I3 for a number ofhours corresponding to the numbers in register. When the zeros of thetwo scales are in register the contact I3 is so positioned with relationto contact I2 that the contact fingers cannot simultaneously engage bothcontacts. This adjustment is made to prevent automatic de-icing.

The motor M of the refrigerator has a circuit including two wires 26 and21 joined to a plug 28 for connection to line wires. Wire 26 leadsthrough the control device D to the motor M. Wire 21 has a switch 29normally held closed by a spring 30 and adapted to be opened by theautomatic control device. From said switch, wire 21 leads through theordinary control device D to the motor. The switch 29 is opened againstthe spring resistance by a solenoid 3| controlled by the automaticdevice. One end of the solenoid coil has a circuit connection 32 withwire 21 and also a connection 33 with a brush 34 in engagement with thecontact 4 on the clock arbor. The other end of the solenoid coil has acircuit connection 35 with a brush 36 in engagement with the contact 5of the arbor. The clock motor 2 has a circuit connection 31 with thewire 26 at a point in advance of the control device D and a circuitconnection with the wire 21 through a conductor 33 leading to theconductor 33, then through a resistance 33 in conductor 33, and throughthe connection 32. Ordinarily, when the electrical connection betweenconductors 33 and 35 is broken at the contact points of the automaticcontrol device, the current for operation of the clock motor iscompelled to flow through the resistance 33 and thence to the motorthrough conductor 33 When, however, electrical connection between theconductors 33 and 35 is made by the automatic device there isestablished a circuit including the conductors 26, 31, 33, 33 throughthe contacts of the timing device and conductor 35, the solenoid 3I andthe conductors 32 and 27. This circuit avoids the resistance 33 Theresistance 33 permits sufficient current to pass through it for thepurpose of operating the motor 2 when the circuit between the conductors33 and 35 is broken. When. however, that circuit is completed throughthe contacts of the timing device the resistance is sufiicient toprevent the fiow of current and the current then passes from 2! through32, through the solenoid coil and conductor 35 and thence throughconductors 33 and 33 to the motor and from the motor to conductor 26,through conductor 31. The resistance 33 is sui'licient to divert thecurrent through the path of least resistance which path is through thesolenoid coil. When, however, the circuit is broken through theconductors 33 and 35 the resistance 33 is not sufiicient to prevent thepassage of current from 32 to 33. The automatic control device and theswitch 29 are preferably enclosed in a suitable casing 38 to form acompact unit.

When no de-icing period has been selected the zeros of the dials I 5 andI 6 are in register and the contact I3 is then so disposed with relationto the contact I2 as to prevent simultaneous engagement of the contactfingers 6 and "I with said contacts. The automatic control device isthen incapable of closing the circuit of the solenoid 3| so that theswitch 29 is held closed by its spring and the motor M is operated,subject only to the control device D. The clock motor 2 is operatedthrough its circuit connection independently of both the control deviceD and the automatic control device and the hand of the clock traversesthe dial 22 without interruption. At the front of the casing 38 is arotatable knob 39 having gear connections 40 with the clock mechanismfor setting the hand when necessary.

To pre-select a time to interrupt the operation of the refrigerator andallow an accumulation of ice to melt from the freezing unit, the dial I5is rotated to bring the pointer 23 of its connected contact plate I0into register with the designation of the selected day on the dial 22and also into register with the mark of the hour selected for theconclusion of the cle-icing period. Then,the duration of the de-icingperiod is predetermined by rotating the central dial I6 relatively todial I5 to bring the desired hour numbers on said dials in register.When the clock-driven contact fingers 6 and I engage both the contactsI2 and I3 the contact fingers will be electrically connected through theplates I0 and I I to close the solenoid circuit and open the switch 29.The contact fingers 6 and I will remain in simultaneous contact withtheir respective contacts I3 and I2 for the number of hours indicated bythe registering numbers, and the switch 29 will be held open by thesolenoid for that period and the control circuit of the motor M will bebroken. When either of the contact fingers moves out of engagement withits respective contact the solenoid circuit is broken and the switch 29is closed by its spring to start the motor. In Fig. 3 the dials l5 andI6 are shown adjusted for a de-icing period to occur on Sunday. Thepointer 23 is shown adjusted for the conclusion of the de-icing periodat 6 p. in. Sunday and the 12 of dial [6 is in register with the 12 ofdial IS. The de-icing period will then continue for twelve hours, from 6a. m. to 6 p. m. The dials may remain set for automatic recurrence ofthe de-icing period on the same day of successive weeks or they may bere-set to select a convenient day and a convenient hour whenrefrigeration is not required. The automatic device is readily cut outof service when the de-icing period has not been decided upon by merelyturning the central dial I 5 to register its 0 with that of the dial 16.

While I have shown and described my invention as employed in connectionwith an electric refrigerator it may be employed to control other typesof mechanical refrigerators.

What I claim is:

1. A control mechanism for an electric circuit, comprising an automaticcontrol apparatus presettable to close said circuit at a predeterminedtime and for a predetermined duration and comprising a motor, a pair ofcontacts insulated from each other and rotatable in unison about acommon axis through one complete circle a week by said motor, a pair ofadjustable contacts constantly electrically connected and adapted formanual rotative adjustment in unison co-axially of said motor-drivencontacts and being respectively engageable by the latter, one of saidadjustable contacts being rotatably adjustable manually relatively tothe other to different positions for varying duration of simultaneouscontact of the motor-driven contacts with the adjustable contacts, acircular dial concentric with the axis of the contacts and indicatingthe days of the week and the hours of the days, the adjustable contactsbeing adjustable in unison with reference to said dial to pre-select theday and hour for closing the circuit, and dial. means to indicate thedegree of relative adjustment of the adjustable contacts and theduration of the closed circuit period.

2. A control mechanism for an electric circuit, comprising an automaticcontrol apparatus presettable to close said circuit at a predeterminedtime for a predetermined duration and comprising a motor, a pair ofcontacts insulated from each other and rotatable in unison about acommon axis through one complete circle a week by said motor, a pair ofadjustable contacts constantly electrically connected and adapted formanual rotative adjustment in unison coaxially of said motor-drivencontacts and being respectively engageable by the latter, and a circulardial concentric with the axis of the contacts and indicating the days ofthe week and the hours of the days, the adjustable contacts beingadjustable in unison with reference to said dial to pre-select the dayand hour for closing the circuit.

3. A control mechanism for an electrical circuit, comprising anautomatic control device presettable to close said circuit at apredetermined time and comprising a plurality of concentric dialsincluding a fixed outer dial having a circular series of indications ofthe days of the week and the hours of the days, a circular rotatableintermediate dial having a series of equally spaced numbered hourdesignations therearound, a circular inner dial rotatable with saidintermediate dial and also rotatable relatively thereto and havingtherearound a series of equally spaced hour designations numberedsimilarly to the designations on the intermediate dial but spaced adifferent distance part, an index registrable selectively with the dayand hour indications by rotation of said intermediate dial, a motor,electrical contact means rotatable by said motor, and contactsadjustable by rotation of said inner and intermediate dials andcooperable with said motor driven contact means to cause the closing ofsaid circuit at the time indicated on the outer dial by said index andfor a duration indicated by corresponding registered hour numbers on theintermediate and inner dials.

4. A pre-settable time switch mechanism to control an electric circuit,comprising a motor, a pair ofcircuit closing elements rotatable by saidmotor in unison and at a uniform rate about a common axis, a pair ofadjustable circuit closing elements both adapted for manual rotativeadjustment coaxially of said motor driven elements and beingrespectively engageable by the latter to close the circuit, one of saidadjustable elements being rotatably adjustable manually relatively tothe other to diiferent positions for varying duration of circuitclosure, a fixed circular time indicating dial concentric with the axisof the circuit closing elements to indicate the adjustment of one ofsaid adjustable elements to pre-select the time of circuit closure, andmeans to indicate the degree of relative adjustment of the adjustableelements and the duration of the closed circuit period.

5. A pre-settable time switch mechanism to control an electric circuit,comprising a motor, a pair of circuit closing elements rotatable by saidmotor in unison and at a uniform rate about a common axis, a pair ofadjustable circuit closing elements both adapted for manual rotativeadjustment coaxially of said motor driven elements and beingrespectively engageable by the latter to close the circuit, one of saidadjustable elements being rotatably adjustable manually relatively tothe other to different positions for varying duration of circuitclosure, a fixed circular time indicating dial concentric with the axisof the circuit closing elements to indicate the adjustment of one ofsaid adjustable elements, to pre-select the time of circuit closure,means to indicate the degree of relative adjustment of the adjustableelements and the duration of the closed circuit period, and manuallyrotatable means to adjust said adjustable elements from in front of saiddial and said indicating means.

6. A pre-settable time switch mechanism to control an electric circuit,comprising a motor, a pair of circuit closing elements insulated fromeach other and rotatable by said motor in unison and at a uniform rateabout a common axis, a pair of adjustable circuit closing elementsadapted for manual rotative adjustment in unison coaxially of said motordriven elements and being respectively engageable by the latter to closethe circuit, one of said adjustable elements being rotatably adjustablemanually relatively to the other to different positions to vary theduration of circuit closure and also to prevent circuit closure, a fixedtime indicating dial having a circular series of graduations concentricwith the axis of the switch closing elements and indicating the days ofthe week and the hours of the days, means to adjust the adjustablecircuit closing elements in unison with reference to said dial topre-select the time of circuit closure, and additional dial means toindicate the degree of relative adjustment of the adjustable elementsand the duration of the closed circuit period.

7. A pre-settable time switch mechanism to control an electric circuit,comprising a plurality of concentric dials including a fixed outer dialhaving a circular series of time indications, a rotatable dial having aseries of equally spaced numbered time indications around its axis,another rotatable dial also having a series of equally spaced timeindications around its axis and munbered similarly to the timeindications on said first rotatable dial but spaced a diflerent distanceapart, an index registerable selectively with the time indications onsaid fixed dial by rotation of one of said rotatable dials, circuitcontrol elements operatively connected to said rotatable dials forrotative adjustments in unison by rotating said dials in unison and forrelative rotative adjustment by rotating one of the rotatable dialsrelatively to the other to vary the times of circuit closure and circuitopening as indicated by the position of said index with relation to thefixed dial and by the registration of correspondingly numberedgraduations on the rotatable dials, a motor, and circuit control meansrotatable by said motor and cooperable with said adjustable elements toefiect the circuit closure and opening at the times indicated on thedials.

8. A time switch mechanism to control an electric circuit, comprising aplurality of concentric dials including a fixed time indicating dial, atime indicating dial rotatively adjustable with reference to said fixeddial, and a time indicating dial rotatively adjustable with reference tosaid first adjustable dial, motordriven circuit-closing means, andcircuit closing means connected to said adjustable dials and adjustablethereby to cooperate with said motor-- driven circuit-closing means toclose and open the circuit times in accordance with the adjustments ofsaid rotatively adjustable dials.

9. A pre-settable time switch mechanism to control an electric circuit,comprising a pair of circuit controlling elements both rotatablyadjustable and one rotatably adjustable relatively to the other, meansto indicate said relative adjustment including a dial fixed to rotatewith one of the elements and having a series of equally spaced, numberedtime indications around its axis and another dial fixed to rotate withthe other element and also having a series of equally spaced timeindications around its axis numbered similarly to said time indicationson the first dial and registerable selectively therewith but spaced adifferent distance apart, and power-driven circuit control meanscooperable with said adjustable elements to eifect closing and openingof the circuit at times in accordance with the adjustments of saidelements.

10. A time switch device comprising a panel having a circular aperture;an annular member rotatably fitted in said aperture and bearing againstthe forward face of the panel around said aperture; a central diskrotatably fitted in said annular member and bearing the forward facethereof; an aperture-d plate bearing against the rear face of the panelaround the margin of the panel aperture and locked for rotation withsaid annular member and bearing an electrical contact; a rear platebearing against the rear face of said apertured plate and locked forrotation with said disk and bearing an electrical contact, said twocontacts being spaced outward from the axis of rotation of the said diskand annular member, whereby they may be adjusted around an axis byrotation of the annular member and disk; a tension spring centrallyconnecting said rear plate and disk for the purpose set forth; and powerdriven circuit-closing meansl cooperable with said contacts to close andopen a circuit at times according to the adjustments of the contacts.

11. A pre-settable time switch mechanism to control an electric circuitcomprising a motor, circuit-controlling means rotatable by said motorabout an axis, a pair of adjustable circuit-controlling devices eachmounted for rotative adjustment coaxially of said motor drivencircuitcontrolling means and cooperable with the latter to close andopen the circuit at times according to the adjustments of saidadjustable devices, a spring holding said adjustable devices in mutualcontact to form a yieldable frictional operative connection between saidadjustable devices enabling them to be rotatably adjusted in unison andpermitting one device to be rotatably adjusted relatively to the other,a circular time-indicating dial, indicating means cooperable with saiddial to indicate the adjustments of one of said adjustable devices, andcooperable time-indicating means borne by said adjustable devices toindicate their relative adjustments.

ROLAND R. NYDEGGER.

